Question

Make a table. Lay the 100 pennies with heads facing up in the bottom of the box. In the first table row (Trial #1), record that 0 pennies were removed (none of them are tails up). Then, record that 100 heads up pennies are left in the box. With 100 pennies showing heads up in the box, close the box and shake it for 3 seconds, then place it on a flat surface. Open the box and count all of the pennies that are now tails up. Remove them as you count. Double check your count and then record the number of pennies you removed in the table (Trial #2). Count the pennies in the box that are still heads up and record that in the table. This is the first half-life of pennium. Repeat Step 3 four more times, each time closing the lid on the remaining heads up pennies and shaking the box for 3 seconds. Each time, be sure to take out the tails up pennies and record the count in the table. Each trial is a half-life of pennium.

Data:

Trial #1- 0 tails and 100 heads. Trial #2- 24 tails and 76 heads. Trial #3- 14 tails and 62 heads. Trial #4- 21 tails and 41 heads. Trial #5- 18 tails and 23 heads. Trial #6- 6 tails and 17 heads.

Questions:

What is the half-life of pennium in your experiment?

Do you think shaking pennies in the box was a realistic simulation of half-lives? Why or why not

Answer 1

No, I don't think shaking pennies in the box was a realistic simulation of half lives because shaking of pennies is a random process whereas to calculate half life there must be a proper rate constant of the reaction. Half life is defined as the time at which the initial amount of substance is reduced to half of its value.